From ec6e0ea3bdf82ee9761d324c011c3627821f7410 Mon Sep 17 00:00:00 2001 From: Anton Vorontsov Date: Fri, 27 Jun 2008 23:04:13 +0400 Subject: [PATCH] [MTD] [NAND] fsl_elbc_nand: implement support for flash-based BBT This patch implements support for flash-based BBT for chips working through ELBC NAND controller, so that NAND core will not have to re-scan for bad blocks on every boot. Because ELBC controller may provide HW-generated ECCs we should adjust bbt pattern and bbt version positions in the OOB free area. Signed-off-by: Anton Vorontsov Acked-by: Scott Wood Signed-off-by: David Woodhouse --- drivers/mtd/nand/fsl_elbc_nand.c | 34 +++++++++++++++++++++++++++++++- 1 file changed, 33 insertions(+), 1 deletion(-) diff --git a/drivers/mtd/nand/fsl_elbc_nand.c b/drivers/mtd/nand/fsl_elbc_nand.c index 99dc2be620..5f1bc5ea2a 100644 --- a/drivers/mtd/nand/fsl_elbc_nand.c +++ b/drivers/mtd/nand/fsl_elbc_nand.c @@ -130,6 +130,34 @@ static struct nand_bbt_descr largepage_memorybased = { .pattern = scan_ff_pattern, }; +/* + * ELBC may use HW ECC, so that OOB offsets, that NAND core uses for bbt, + * interfere with ECC positions, that's why we implement our own descriptors. + * OOB {11, 5}, works for both SP and LP chips, with ECCM = 1 and ECCM = 0. + */ +static u8 bbt_pattern[] = {'B', 'b', 't', '0' }; +static u8 mirror_pattern[] = {'1', 't', 'b', 'B' }; + +static struct nand_bbt_descr bbt_main_descr = { + .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE | + NAND_BBT_2BIT | NAND_BBT_VERSION, + .offs = 11, + .len = 4, + .veroffs = 15, + .maxblocks = 4, + .pattern = bbt_pattern, +}; + +static struct nand_bbt_descr bbt_mirror_descr = { + .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE | + NAND_BBT_2BIT | NAND_BBT_VERSION, + .offs = 11, + .len = 4, + .veroffs = 15, + .maxblocks = 4, + .pattern = mirror_pattern, +}; + /*=================================*/ /* @@ -767,8 +795,12 @@ static int fsl_elbc_chip_init(struct fsl_elbc_mtd *priv) chip->cmdfunc = fsl_elbc_cmdfunc; chip->waitfunc = fsl_elbc_wait; + chip->bbt_td = &bbt_main_descr; + chip->bbt_md = &bbt_mirror_descr; + /* set up nand options */ - chip->options = NAND_NO_READRDY | NAND_NO_AUTOINCR; + chip->options = NAND_NO_READRDY | NAND_NO_AUTOINCR | + NAND_USE_FLASH_BBT; chip->controller = &ctrl->controller; chip->priv = priv; -- 2.39.5